Vaginal tampon



United States Patent 3,091,241 VAGINAL TAB EON William R. Keilett, Menasha, Wis., assignor to Kimberly- Clarir Corporation, Neenah, Wis, a corporation of Delaware No Drawing. Filed Aug. 26, 1959, Ser. No. 836,081 2 Claims. (Cl. 128-270) This invention relates to improvements in catamenial devices such as vaginal tampons and sanitary napkins.

An important object of the invention is to provide improvements in catamenial devices of the type used primarily for normal menstrual use as well as the type used primarily for therapeutic treatment of the female genitalia, and particularly the vaginal tract.

Another object is to provide a medicated catamenial tampon which effectively maintains or restores the normal ecological balance of the vagina, prevents putrefactive activities of microbial growth, is non-irritating and non-toxic, and which may safely be used without a medical prescription.

A further object is to provide a catamenial tampon which acts as a physiological biostat or automatic controller for any microorganic imbalance which may exist in the immediate area of use.

Another object is to provide an improved medicated catamenial device which remains highly effective as a deodorant during a normal use period.

Other objects and advantages will become apparent to persons skilled in the art, as will various modifications thereof without departure from the inventive concepts defined in the appended claims.

There exists in the female body a complicated process which maintains the vagina and other related delicate areas in a normal healthy state most of the time. During the menses, however, this normal healthy state of the vaginal area is disrupted to some extent and at such time the vagina may become more susceptible to infection than usual. Such infection is commonly called vaginitis, a condition which develops more easily in some women than others, and which is frequently associated with.

their monthly discharge period. The danger of infection increases during this time because foreign microorganisms or other outside sources of infection may be introduced through careless handling of sanitary napkins, or more especially, through careless handling and insertion of absorbent tampons. The concept herein taught minimizes the possibility of such infection occurring.

The normal vaginal environment in the adult female resuits from a complicated harmony of hormonal, cytologic, and bacterial factors which develop at puberty, when glycogen is deposited in the vaginal wall and the secretion becomes acid. The normal flora of the vagina seems to depend largely on the glycogen content of the vaginal epithelium, which later is further dependent on ovarian activity. The flora of the vagina is mixed, consisting of varied staphylococci, streptococci, coliform and diphtheroid bacilli, a few yeasts and fungi but predominantly of Bacillus vaginalis or Ddderleins bacillus. The normal vaginal secretion has a marked bactericidal action, largely ascribed to the presence of lactic acid, although other factor probably are concerned. The lactic acid itself is derived from the glycogen, partly as a result of natural enzymes, but mainly due to the fermentative activity of Ddderleins bacillus.

Vaginitis is often the result of an unbalancing of these factors and frequently is evidence of altered microflora or physiology in the vagina. When the normal condition is altered, the pH generally increases and an inflammatory condition can result, often caused by the predominance of a yeast-like growth, Candida albicans (moniliasis), and sometimes by a protozoa, Trichomonas vaginalis.

\ 3,91,241 Patented May 28, 1963 Indications are that these disease have become more prevalent in recent years, probably as the result of increased antibiotic therapy which often upsets the normal bacterial balance.

Under normal conditions, estrogen secretion stimulates the growth of glycogen bearing epithelial cells. These cells metabolize and degenerate, releasing lactic acid. This acid creates a favorable environment for normal vaginal flora, including the lactobacillus, which perpetuates the cycle in turn by reacting on the glycogen bearing cells. The resulting pH is from 3.8 to 4.5 which is generally considered the most favorable condition for maintenance of normal flora. At that pH, the vagina normally harbors numerous species of microorganisms which, when present in a balanced ecology, play a beneficial role in providing protection and resistance to infection.

During menstruation, a slightly alkaline pH is frequently established with attendant sloughiug of epithelial tissue. Thus, less lactic acid is released and the pH tends to remain alkaline. Such conditions favor the onset of vaginitis, since in an alkaline environment an overgrowth of putrefactive microorganisms may develop followed by inflammation.

The present invention provides an eflicient means for therapeutic treatment of the vaginal tract at the time in the monthly cycle when such treatment is most beneficial. It serves to reduce to a minimum the possibility of contracting vaginitis during menses and serve further to relieve such conditions, if already developed, by providing a specially treated absorbent tampon which acts as a physiological biostat, i.e. automatically maintains and controls the normal ecological balance of the vagina.

According to this invention, there is provided to perform this unusual biostatic function, an absorbent tampon containing controlled amounts of glyceryl triacetate (triacetin).

The biostatic effect of triacetin, as observed by Dr. S. G. Knight of the University of Wisconsin is reported in Johnson et a1., A.M.A. Arch. Dermatology, vol. 74, pages 73-75 (1956); Knight, Antibiotics and Chemotherapy, vol. VII, pages 172-4 (1957); Knight, 11. Investigative Dermatology, vol. 28, pages 363-6 (1957); and Burack et 211., ll. Investigative Dermatology, vol. 30, pages 197-9 (1958).

Glyceryl triacetate, or triacetin, is readily broken down into glycerol and acetic acid by the enzymatic action of esterase. 'Esterase is abundantly present in the vaginal epithelium and serum released during menses. The enzymatic action of the esterase is in turn controlled by the pH of the environment, and is more active when the pH is on the alkaline side. Since the pH of the vaginal area moves toward the alkaline side during menstruation, i.e. to a pH of about 6 to 8, the enzymatic activity of esterase automatically increases and attacks the triacetin carried by the tampon, which releases acetic acid rapidly. As the acid is released, the pH drops to a level of about 4 causing a decrease in esterase activity which, in turn, slows the breakdown of triacetin and coincident release of acid. As the normal menstrual function goes on, its tendency toward an alkaline environment continues to neutralize any acids present causing the pH to rise again and reinitiate esterase activity. This, in turn, releases more acetic acid to again lower the pH. II he decreasing pH also automatically keeps the acetic acid in physiologic bounds by inhibiting the rate of esterase activity and subsequent release of more acid. This constant low concentration of acetic acid acts as a continuing mild biostatic agent which prevents multiplication of harmful microorganisms without detrimental effect on the normal vaginal flora. The triacetin is thus not limited to a 3 ""s'in'glea'ctive 'cyclefbutmaintains its therapeutic effect untilexhausted.

This interrelated cooperation of the enzymatic action ofthe estera se and the decomposition of the triacetin, "therefo aictsjfavorably in'restoring the pH of the vagina toitsn frnal'jhealthy range and maintaining it there. It "has"be'en found thatthe concentration of acetic acid so produced is not irritating or harmful to'the tissues, even over"e iter 1dedtime' periods. The mild biostatic action "isnotjsperrnicidalgnor doesit attackthe useful microf ganisms usually present. The'interaction which takes place is "ccim'para'ble to'theuse of a constant vinegar doiiche. Thisactionof maintaining the pH of" the vagina Withinfitsnormal acid range is most important in preserying its'ecological'balance. V h The fungicidaland 'bactericidalvalues of the fatty acids, including acetic"acid,"hjave been known for many years. "fHowever,"they have'not found wide use'because they are irritating"andjcorrosive' at' high'concentration, and lose their effectivenesscomparatively fast either because they may volatilize too fast, or diffuse away from the'site of an "inf'e'ctiombeing treated; orbec'ome "neutralized to their relatively inefiectivesalts. The discovery of the f unique action of'triacetin has made it possible to utilize 'it {as {self-regulating agent, mild enough to be biostatic f'ra'ther tharfbibcidal, which does not have the abovelisteddisaizlv'a'ntages. The self=regulating"action assures the m'aintenance of a therapeutic level of free fatty acid f at thesite of infection orTpotential' infection, and at the "same trrne'prevents irritation which might be caused by overtre'atnaentsuchas' -too high a concentration of acid. Many types of'tre'atment forv a'ginitis' have been tested ja'nd usedimthepast; butnonehas been universally f'satisfaetory. "'Local treatnient'of infectedareas has in- "chidedtheuseflofsulfa cream; 'arsenics or picric acid derivatives; lactose "tablets; 'silvennitrate; "gentian violet; antibio tics; mildacid douchesjand others. Antibiotics f'such" a ur'eornycin';chldramphenicol, penicillinfdihydrostreptomycinandterramycin' have been used both orally andpare'nterally with 'somelocal'andfavorable effect'on abnormal vaginal flora, but, as DOtGd bCfOTQ' lThlS often "upsets theecolo'gical' balance and may cause side effects "because of sensitivity and the like. I V

The'use ofnonfabsorbent vaginal inserts such'as suppositories' or'medicated lambs wool'is not practical during'the menstrual period, although they have been used atsuch time, but only with difiiculty. Now, the combina- "'tion ofan' absorbe'nt tampon with a new therapeutic'agent for vaginitis provides a convenient methodfor'the local treatment of infection during menstruation as well as at "other times. 7 t V Thus it can be seen 'that'fan absorbent tampon containing tr iacetin is far superior to ordinary tampons. If it is 'nse'd un-derjc'onditions of normal pH', it will absorb body fluids effic'iently as ordinary tampons do. However, if "conditionsffoster analkaline pH the tampon will provide therapeutic action by releasing acetic acid in close proximity to the's'ource of infection, The acetic acid acts as f a bacterio'stat ended the same time tends to return the tissue to'a normal pH of between about 3.8 to 4.5 and "encourage re-establishment of the normal bacterial flora which 'aidi'n resisting" further infection. The coincident "releaseof glycerol i s also beneficial to the vaginal area because of its well known emollient effect on the skin or r'nucousinembrane. V

'Arr additional "advantage is that triacetin functions as a deodorant by inhibiting the'overgrowth of putrefactive microorganisms, thus stopping odors by destroying their source rather than'rnerelymasking odors which already "exist.

The triac'etin also 'acts' as a softening agent on fibers, V "fabrics, and sponges treated therewith, giving them a smoother; softer finish. This is an especially desirable property for catamenial'devices generally. It provides easier insertion fortampons thus treated, and gives more (1) Mild baceteriostatic properties, i.e. the arresting of bacterial growth,

? 2) Some selective action against certain microorganisms particularly yeasts and fungi frequently associated with vaginitis, V

(3) A safe threshold odor value (the minimum concentration of test material required to inhibit odor under standard test conditions).

Qther testsfin which "tampons' were treated with triacetin in" controlled amounts, indicated concentrations of"tr'iacetin starting as low as 0.25 percent by weight, based oil weight of the, absorbent material being treated, "had 'be neficial effects. Excellent results were obtained .with'concent'ritions of between 1 percent and 2.5 percent triacetinbywei ght. Howeverfthe invention is not so limited, and under certain conditions, such as in tampons specifically designedfof therapeutic use, concentrations up to Spencent and higher' may be employed. No bactericidal action (killing ofmicroorganisms) results from employment of concentrations :up to 5 percent. Further, 'When'used insuchconcentration with tampons, there was 5' no 'spermicidal action.

If the concentrationsof triacetin are present in excess of 5 percent by' weight,'the tampon often takes on "'an' oily appearance which might be objectionable for ordinary menstrual useybut is readily acceptable when 40 used forrnedicationpurposes Vaginal tampons jsuitablefor use in'this' invention are usually madeofabsor bent fibers, including natural and synthetic fibers: compressed-into a un itary body of a j .sizewhich may easily beinserted into the vaginal cavity. They are normally made in an elongated cylindrical form inorder that'theyfmay have a sufficientlylarge body'of material-to provide the required absorbing capacity, but may'be'made'iri a variety of shapes. The tampon may or may not be compressed,"although compressed types are now generally preferred. "The tampon described in U.S. Patent 2,761,449, dated September 4, 1956, is

typical. {This patentshows'a tampon made of various fiberblendsincluding both absorbent and nonabsorbent fibers, which'may 'or may not have a suitable jacket or wrapper. Tampons of thistype may 'be treated with triacetinin various ways. For example, the wrapper.

only maybe impregnated; the absorbent fibers only may be impregnated; or the entire tampon assembly may be Newer style tampons" made from absorbent microporous sponge'material' such as described in US. Patent 2,880,726, datedApril 7, 1959, may'also be treated in the manner" herein described.

a 'Any conventional method may be used for applying 65 the mean to" the absorbentelements. One method is by passing the material to be impregnated through a liquid bath of pureitriacetin. Dilution with solvents and the like is ordinarily not necessary when high concentrations are desired,;since triacetin is a clear liquid slightly more viscous than water. Howeven'to more easily control the amount picked up by the material being treated,

solvents, such as ethyl alcohol or ether or their aqueous solutions, may-be used todilute the'impregnating bath. Unitary tampons without separate wrappers may be dipped directly into the bath and air dried, when n ecessary to remove any volatile solvents. For compressed tampons, impregnating of any of its elements is best done before compressing.

If the tampon is provided with a separate permeable wrapper, the Wrapper alone may be impregnated by passing it through a triacetin bath on conventional textile padding equipment, or the like, before the tampon is Wrapped and compressed. Conventional drying methods for fabrics may also be used when necessary. Obviously the complete assembly could also be dipped as with unitary tampons.

It is not necessary to impregnate the entire absorbent body of the tampon with the triacetin. Optimum results both economically and functionally, are obtained by concentrating the material on or near the outer surface Where it will be most effective during use. Some migration of the triacetin takes place in the treated pad, as is true of all glycerol-like substances over a period equivalent to normal shelf life, but the highest concentrations will remain in the general area where it has been applied originally.

Another method found useful for applying the triacetin is to treat the loose absorbent fibers before they are formed into an absorbent pad by soaking them in the triacetin, subsequently drying the fibers where necessary, and forming the treated fibers, alone or in combination with untreated fibers, into pads of desired size and shape. The loose fibers could also be treated by spraying with triacetin in the forming chamber when air-forming methods are used to form pads.

It is also contemplated to use the triacetin in combination with externally worn sanitary napkins. When the wrapper or external elements of such napkins are treated as taught herein, the napkins have a softer cosmetic feel and may be worn with more comfort. In addition there is provided the deodorizing action previously described, along with some therapeutic value which develops wherever the napkin is in contact with the external genitalia. This is useful in cases where the latter are easily irritated or subject to minor infections. When the internal elements of sanitary napkins only are treated with triacetin, the deodorizing properties predominate.

What is claimed is:

1. A compressed vaginal tampon adapted for easy insertion and expansion within the vaginal cavity under normal conditions of use and for absorbing and retaining catamenial fluid While maintaining a normal ecological balance in the cavity during menses, said tampon comprising, as the fluid absorbing and retaining means, a compressed absorbent body, and as means for maintaining said normal ecological balance, glyceryl triacetate, said glyceryl triacetate being present at least in the outer peripheral area of said body in the amount of from about 0.25 percent to 5.0 percent by weight based on the total Weight of said body, said tampon being nontoxic, non-irritating, and non-spermicidal in use.

2. A compressed vaginal tampon adapted for easy insertion and expansion within the vaginal cavity under normal conditions of use and for absorbing and retaining catamenial fluid while maintaining a normal ecological balance in the cavity during menses, said tampon comprising, as the fluid absorbing and retaining means, a compressed absorbent body comprised of absorbent fibers and an outer wrapper of absorbent fluid pervious material, and as .themeans for maintaining said normal ecological balance, glyceryl triacetate, said glyceryl tr-iacetate being present .at least in the outer peripheral area of said body in the amount of from about 0.25 percent to 5.0 percent by weight based on the total weight of said body, said tampon being non-toxic, non-irritating, and non-spermioidal in use.

FOREIGN PATENTS Great Britain Apr. 6, 1955 OTHER REFERENCES 

1. A COMPRESSED VAGINAL TAMPON ADAPTED FOR EASY INSERTION AND EXPANSION WITHIN THE VAGINAL CAVITY UNDER NORMAL CONDITIONS OF USE AND FOR ABDORBING AND RETAINING CATAMENTAL FLUID WHILE MAINTAINING A NORMAL ECOLOGICAL BALANCE IN THE CAVITY DURING MENSES, SAID TAMPON COMPRISING, AS THE FLUID ABSORBING AND RETAINING MEANS, A COMPRESSED ABSORBENT BODY, AND AS MEANS FOR MAINTAINING SAID NORMAL ECOLOGICAL BALANCE, GLYCERYL TRIACETATE, SAID GYLCERYL TRIACETATE BEING PRESENT AT LEAST IN THE OUTER PERIPHERAL AREA OF SAID BODY IN THE AMOUNT OF FROM ABOUT 0.25 PERCENT TO 5.0 PERCENT BY WEIGHT BASSED ON THE TOTAL WEIGHT OF SSAID BODY, SAID TAMPON BEING NONTOXIC, NON-IRRITATING, AND NON-SPERMICIDAL IN USE. 